I just wanted to know the earliest Buddhist reference to the Bijakshara "Om" and the Syllables "Svaha".

Is there any Mahyana-specific explanation for "Om" & "Svaha" ? These are virtually contained in every other Dharanis & Mantras of Mahayana. I am expecting some early Mahayana Sutra to contain the explanation for the use of these syllables.

I am aware Om is explained in Vajrayana as the Vak, Kaya & Citta of the Buddhas. (If I remember from E-Sangha, Eijo quoted an east asian Tantric text where "Om" was considered referring to the Trikayas). I presume, the Tantric texts are dated much later, hence would have had time to come up with an Buddhist association for these.

From HHDLIt is very good to recite the mantra OM MANI PADME HUM, but while you are doing it, you should be thinking on its meaning, for the meaning of the six syllables is great and vast. The first, OM is composed of three letters, A, U, M. These symbolise the practitioner’s impure body, speech and mind; they also symbolise the pure exalted body, speech and mind of a Buddha.

In order to ensure my mind never comes under the power of the self-cherishing attitude,I must obtain control over my own mind. Therefore, amongst all empowerments, the empowerment that gives me control over my mind is the best,and I have received the most profound empowerment with this teaching.-Atisha Dipamkarabrtsal ba'i bkhra drin

I just wanted to know the earliest Buddhist reference to the Bijakshara "Om" and the Syllables "Svaha".

Is there any Mahyana-specific explanation for "Om" & "Svaha" ? These are virtually contained in every other Dharanis & Mantras of Mahayana. I am expecting some early Mahayana Sutra to contain the explanation for the use of these syllables.

I am aware Om is explained in Vajrayana as the Vak, Kaya & Citta of the Buddhas. (If I remember from E-Sangha, Eijo quoted an east asian Tantric text where "Om" was considered referring to the Trikayas). I presume, the Tantric texts are dated much later, hence would have had time to come up with an Buddhist association for these.

V

What is the point in wondering and asking when some or other aspect of Dharma has first manifested on planet Earth? Enlightenment/nirvana is timeless, beyond time, and beyond history. But no one seems to believe this! They only believe in old scraps of paper or pieces of treebark. It is a useless and time consuming search. When the eternal and timeless Nirvana is always present, why turn your back to it!